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  1. UY BAN NHAN DAN QU~N 5 TRUONG TRUNG CAP NGHE KY THU4T CONG NGH"¢ HUNG VUONG r ' GIAOTRINH Dung sai - Do hrirng kY thu~t ' r Nghe: Cat gqt kim lo~i TRINH DO• TRUNG CAP TPHCM-2019
  2. 1 LOI GIOI Tmiu Giao trinh Dung sai - do luong ky thu~t dugc bien soi;tn nhim cung c~p cho h9c sinh h~ Trung c~p ngh@ c~t gc;>t kim loi;ti nhfrng kiSn thuc nhu sau: - Ban ch~t cua tinh d6i Ik trong l~p ghep. - H~ th6ng dung sai l~p ghep theo TCVN 2244-2245. - Tra, tinh toan dung sai kich thu6c, dung sai hinh di;tng va vi tri, d9 nham b@ m~t va dung sai l~p ghep cac m6i ghep thong dvng. - Dung sai m9t s6 chi tiSt diSn hinh va cac kich thu6c c§.n chu y khi chS ti;to. - Ky hi~u dung sai kich thu6c, dung sai hinh di;tng va vi tri, nham b@ m~t Ieh ban ve. - Cac phuong phap do, d9c, su dvng, bao quan cac loi;ti d\lllg C\l do thong d\lllg va ph6 biSn trong nganh ca khi. Giao trinh g6m 06 chuong cung c~p nhfrng kiSn thuc v@ dung sai - do luong ky thu~t trong linh Vl)'C c~t g9t kim loi;ti Trong qua trinh bien SOl;lll, tac gia xin chan thanh cam on quy Th§.y co da g6p y nhi~t tinh dS giao trinh ngay cang hoan thi~n hon nfra Qu~n 5, ngiiy thang nam 20 ...
  3. 2 MVCLVC BEMVC TRANG 1. Loi gioi thi~u 2 2. Chll'ong 1: Khai ni~m cO' ban v~ dung sai lip ghep 4 3. ChU'ong 2: Dung sai lip ghep cac b~ mJt tron 14 4. Chll'ong 3: Cac y~u tel hinh hQc cu.a chi ti~t 34 5. Chll'ong 4: Dung sai va lip ghep cac chi ti~t di~n hinh 54 6. Chll'ong 5: Chu6i kich thll'O'C 78 7. Chll'ong 6: Bo lll'crng ky thu~t 92 8. Tai li~u tham khao 119
  4. 3 CHUONG 1: KHA1 NI¥M CO BAN VE DUNG SAi LAP GHEP Gi6i thi~u: Chuong nay nhrtm cung cfip cho h9c sinh nhfrng kien thuc v€ khai ni~m v€ dung sai Hip ghep trong ngh€ c~t g9t kim lo~i M\IC tieu: - Trinh bay duqc ban chfit cua tinh d6i lfin trong l~p ghep. - Li~t ke duqc cac lo~i l~p ghep. - Phan bi~t duqc cac h~ th6ng dung sai. N
  5. 4 + Vi m(it kinh tl: Nho c6 tinh d6i lfin chuc nang ma kh6ng cffn phai thie't ke' nhung chi tie't du(Jc tieu chufin h6a. Do d6 giam du'
  6. 5 IIL SAi LiJCH GJ{JJ H~N 1.Khai ni~m Sai l~ch gioi hc:;tn la hi~u dc:;ti s6 giua kich thuoc gioi hc:;tn va kich thuoc danh nghia. 2.Phanlo~i a. Sai l~ch gioi h~n tren (Ky hi?u ES, es) Sai l~ch gioi hc:;tn tren la hi~u dc:;ti s6 giua kich thuoc gioi hc:;tn Ion nha't va kich thuoc danh nghia. ES =Dmax-D ; es= dmax- d b. Sai l~ch gioi h~n duoi (EI, ei) Sai l~ch gioi hc:;tn duoi la hi~u dc:;ti s6 giua kich thuoc gioi hc:;tn nho nha't va kich thuoc danh nghia. EI = Dmin - D ; ei = dmiu- d es ES ei ffinhl .2: Sa d6 bilu ddn kich thu{Jc gi{Ji hr;in va sai lfch gi{Ji hr;in Ghichu: • Sai lf ch gi{Ji hr;in c6 thi ducJng, am hoiJ,c bdng khong. • Sai lf ch gi{Ji hr;in tren luon luon l{Jn hcJn sai lf ch gi{Ji hr;in am • DcJn vt gi{Ji hqn c6 thi la mm hoiJ,c µn 3. Dung sai (kj hi?u T) Dung sai la hi~u dc:;ti s6 giua kich thuoc gioi hc:;tn Ion nha't va kich thuoc gioi hc:;tn nho nha't. = = TD Dmax - Dmin ES - El = = Td dmax - dmin es - ei Ghi chu: • Dung sai luon luon ducJng. • DcJn vt do cua dung sai la mm hoiJ,c µn. 4. Cach ghi kfch thuoc tren ban ve • Kich thuoc danh nghia • Sai l~ch gioi hc:;tn (tren va duoi) • Ta't ca phai cung don vi mm.
  7. 6 2so+o - 02 ,, ,---- Ln Cu 0 0 - s;:i 0 +I 0 - -----o 0 - - ---- 00 0 Cu -I-- f-- - - ----.- ~ 00 ~ ~ 0 & ; ' 80,01±0,02 90 0 20 0 -0 05 -0 2 Vi du : Biet ldch thu6c cua chi tie't lo Ia: cj>50 :::=mm Tinh cac ki'.ch thuac giro.~ va dung sai. Kfch thu6'c thll!C cua lo sau khi gia cong do dll'Q'C la: Dt = ♦49,950 mm, hoi chi tie't 18 dii gia cong c6 d~t yeu c:iu khong ? Gidi: Kfch thu6'c gim. h~ Ian nMt cua lo: Dma.x = DN +ES= 50 + 0,020 = 50,020 mm Kfch thuoc gi6i. hi;m nho nhat cua 16: Dmm =~+EI = 50 - 0,041 =49,959 mm. Dung sai cua lb: TD=ES-EI=0,020-(-0,041)= 0,061 mm Chi tie't 16 d~t yeu cau k:hi ldch thl.WC thi;rc cua no thoa man: Dm.i.o, < Dt ~ Dmax Ta thiy: Dmm =49,959 > Dt =49,950 V~y chl tiet 16 da gia cong khong d~t yeu cau. IV. KHA.I NIEM • VE LAP GHEP: I • Dfnh nghia: Liip ghep la slf ph6i h ph~n may hay m9t may c6 ich. Vi d1:1: Bai 6c liip voi bulong, pittong liip voi xy lanh trong may n6 ... ffinhl.3: Vi dl!, vi ldp ghep s Cac khai ni~m:
  8. 7 Kich thudc danh nghia cua l~p ghep: Trong m(>t l~p ghep, kich thudc danh nghia cua 16 phai biing kich thudc danh nghla cua tnJc va g9i la kich thudc danh nghla cua l~p ghep. D = d ffinhl .4: Vi d¥, vi ldp ghep BS m~t l~p ghep: La bS m~t tie'p xuc giua hai chi tie't l~p ghep vdi nhau. BS m~t l~p ghep du(Jc chia lam hai loi;i.i: bS m~t bao va bS m~t bi bao. BS m~t Uip ghep c6 thl la m~t trl;l hay m~t ph~ng. Chi tietbao B~ IDl!tbao i I -0 II Q --·--/·--- ~ D=d Chi tiet bi bao ffinhl .5: Bi mijt bao va bi mijt ht bao
  9. 8 - D~c tinh cu.a Hip ghep: La hi~u s6 giua kich thuoc bS m~t bao va bS m~t bi bao. D\fa vao d~c tinh cu.a Hip ghep, Nguoi ta chia Uip ghep lam 3 lo,;i.i: 1. Nh6m Hip ghep c6 d() blt (Liip long): La Hip ghep trong d6 kich thuoc bao luon luon Ion hon kich thuoc bi bao. D◊ ho trong la'. p ghep ky hi~u la: S ffinhl.6: Lifp ghep c6 dq ha D~c trung cu.a la'.p ghep nay la: ·+ DQ hd Ion nha't: Smax = Dmax - dmin = ES - ei + D◊ hd nho nha't: Smin = Drrnn - dmax = EI - es + DQ,. . h.,o trung b~nh 1 : S tb = Smax + Smin 2 + Dung said◊ hd: Ts= Smax - Smin =To+ Td 2. Nh6m liip ghep c6 d() doi (Liip chij.tLa la'.p ghep trong d6 kich thuoc bao lu6n luon nho hon kich thuoc bi bao. D◊ doi trong la'.p ghep du9c ky hi~u la N N_.. ffinhl .7: Lifp ghep c6 d
  10. 9 Di:J.c tntng cu.a lip ghep nay la: + D9 doi Ion nha't: Nmax == dmax - Dmin = es - EI + D9 doi nho nha't: Nmin = dmin - Dmax = ei - ES + D9 doi trung blnh: Nth= Nmax + Nmin 2 + Dung sai d9 doi: TN= Nmax - Nmin = To+ Td 3. Nhom Hip ghep trung gian (Liip co d
  11. pm El== 0 duong 0 .. ·Dlfa vao so d6 phan b6 dung sai Hip ghep, c6 th€ xac dinh d~ dang: - La:p ghep c6 d9 hd khi mien dung sai cua 16 n~m tren mien dung sai cua tn;1c - La:p ghep c6 d9 doi khi mien dung sai cua 16 n~m du'oi mien dung sai cua trvc - - La:p ghep trung gian khi mien dung sai cua 16 va mien dung sai cua tflJ.c c6 ph~n chung. • Ke't lu~n: V~y tren so d6 Hip ghep cho chung ta bie't: - H~ th6ng Hip ghep ( 16 ho~c tflJ.c ) Gia tri cua cac sai l~ch gioi h~n - Gia tri cua cac kich thu'oc gioi h~n - D9 hc:1 ho~c d9 doi gioi h~n - Dung sai 16 va dung sai trvc - Ki€u 1a:p. BAI TiP UNG DVNG Cau 1 : Khai nijm v~ kich thu6c danh nghla : a. La kich thu'oc du9c do tfllc tie'p tren chi tie't b~ng cac dvng cv do va phu'ong phap do chinh xac nha't ma ky thu~t c6 th€ d~t du'9c. b. Kich thu'oc danh nghia la kich thu'oc ma dlfa vao chuc nang va dieu ki~n lam vi~c cua chi tie't d€ tinh toan, xac dinh va llfa chc;m theo ttj s6 kich thu'oc tieu chuffn. Kich thu'oc danh nghia phai du'
  12. 11 c. La kich thu'oc Ion nhai va nho nha't gioi h~n trong ph~m vi cho phep ciia kich thu'oc chi tie't. d. La gia ttj bAng s6 ciia d~i ht9ng do chiSu dai theo don vi do du'9c h;ta ch9n. Bon vi do thuong dung la mm nhung khong ghi tren ban ve. Cau 3 : Khai ni?m v~ kfch thztuc th-f/c : a. La kich thu'oc du9c do tn;tc tie'p tren chi tie't bAng cac di;mg C\l do va phu'ong phap do chinh xac nha't ma ky thu~t c6 th€ d~t du9c. b. Kkh thuoc danh nghia la kich thuoc ma dt;ta vao chuc nang va di~u ki~n lam vi~t ciia chi tie't d€ tinh toan, xac dinh va h;ta ch9n theo ttj s6 kich thu'oc tieu chufin. Kich thu'oc danh nghia phai du9c tieu chufin h6a. c. La kich thu'oc lon nha't va nho nha't gioi h~n trong ph~m vi cho phep ciia kich thu'oc chi tiei d. La gia ttj bAng s6 ciia d~i lu'9ng do chi~u dai theo don vi do du9c h;ta ch9n. Bon vi do thu'ong dung la mm nhttng khong ghi tren ban ve. Cau 4 : Khai ni?m v~ dung sai : a. La hi~u d~i s6 gifi'a kich thuoc gioi h~n va kich thuoc danh nghia. b. La hi~u d~i s6 gifi'a kich thu'oc gioi h~n lon nha't va kich thuoc danh nghia. c. La hi~u d~i s6 gifi'a kich thu'oc gioi h~n nho nha't va kich thu'oc danh nghia. d. La hi~u d~i s6 gifi'a kich thu'oc GHLN va kich thu'ocDHNN:-·- Cau 5 : Khai ni?m v~ sai l?ch gi6i hf!,n : a. La hi~u d~i s6 gifi'a kich thuoc gioi h~n va kich thuoc danh nghia. b. La hi~u d~i s6 gifi'a kich thu'oc gioi h~n lon nha't va kich thu'oc danh nghia. c. La hi~u d~i s6 gifi'a kich thu'oc gioi h~n nho nha't va kich thu'oc danh nghia. d. La hi~u d~i s6 gifi'a kich thu'oc GHLN va kich thu'oc GHNN. Cau 6 : Khai ni?m v~ sai l?ch gi6i hgn nho nhift: a. La hi~u d~i s6 gifi'a kich thu'oc gioi h~n va kich thu'oc danh nghia. b. La hi~u d~i s6 gifi'a kich thu'oc gioi h~n lon nha't va kich thu'oc danh nghia. c. La hi~u d~i s6 gifi'a kichthu'oc gioi h~n nho nha't va kich thu'oc danh nghia. d. La hi~u d~i s6 gifi'a kich thu'oc GHLN va kich thu'oc GHNN. Cau 7 : Khai ni?m v~ sai l?ch gim hgn /fin nhift: a. La hi~u d~i s6 gifi'a kich thuoc gioi h~n va kich thuoc danh nghia. b. . La hi~u d~i s6 gifi'a kich thu'oc gioi h~n lon nha't va kich thu'oc danh nghia. c. La hi~u d~i s6 gifi'a kich thu'oc gioi h~n nho nha't va kich thu'oc danh nghia. d. La hi~u d~i s6 gifi'a kich thu'oc GHLN va kich thu'oc GHNN.
  13. 12 Cho chi tiet co kich thu:uc : D = ¢80 _0_046 Cau 8 : Sai ljch giui h,;m lun nhat va nho nhat la : a. ES = 0, EI = -0,046 b. ES = -0,046, EI = 0 ; c. es = 0, ei = -0,046 d. es = -0,046, ei = 0 Cau 9 : Kich thU:uc giui h
  14. 13 CHUONG 2: DUNG SAi LAP GHEP cAc BE MAT TRON . Gioi thifu: Chuong nay nh~m cung cfrp cho h9c sinh nhung ki~n thuc ve dung sai Hip ghep cac b8 m~t tron trong ngh6 cit g9t kim lo~i Mvc tieu: - Trinh bay duqc cac qui dinh lip ghep cua h~ th6ng dung sai lip ghep cac be m~t tron theo tieu chuAn Vi~t nam (TCVN2244-99) - Ghi va d9c duqc cac gia tri dung sai tren ban ve. - Tra thanh th~o cac bang tra dung sai (theo TCVN 2245-99). N{>i dung chinh: I. KRAi NIEM VE MIEN DUNG SAi 1. TR/ SO DUNG SAi Tri s6 dung sai du'QC tinh theo cong thuc : IT = a x i ► i la don vi dung sai, ph1;1 thu(>c vao kich thu'dc danh nghia D. i = 0,451/D + 0,001D ; D ( mm) va i (µm) ► a la h~ s6 chinh xac, ph1;1 thu(>c vao cffp chinh xac. Kich thu'dc cang chinh xac thl a cang nho va ngu'QC l~i. Bang2.1 ·,..._. , , ,.,.? ~ ' ,.._, A. CONG THUC TINH TRJ SO DUNG SAi TIEU CHUAN (IT= ai) VA TRJ SO DON VJDUNGSAli KTDN Ca'p dung sai trnu chuii'n ITS IT6 IT7 ITS IT9 ITlO ITU IT12 IT13 IT14 IT15 IT16 Tren Btn va Cong thuc tfnh dung sai tieu chuii'n (ddn vi micromet) g6m 500 7i lOi 16i 25i 40i 64i lOOi 160i 250i 400i 640i lO00i Tri so'i KhoangKTDN Tren Tr.3 Tr. 6 Tr.IO Tr.18 Tr30 Tr.SO Tr.SO Tr.120 Tr.180 Tr.250 Tr.315 E>.3 0. 6 E>.10 E>.18 E>.30 E>.50 E>.80 E>.120 E>.180 E>.250 E>.315 E>.400 i = 0,451/D +0,00ID 0.55 0.73 0.90 1.08 1.31 1.56 1.86 2.17 2.52 2.89 3.22 3.54 Vi du : Cho hai tr1;1c c6 kich thu'dc d1 = ¢50~:~~~ va d2 = ¢80~:~;~. Hoi chi tie"t nao yeu c!lu d(> chinh xac cao hon? Hu{Jng ddn : Xdc dfnh h~ sff a d7/a vao cong thric : T = ai. · Trong d6: t = es - ei ( ddi v
  15. 14 T = ES - EI (dm vai lb) i tra bdng dl!a vao khodng k{ch thuac (theo bdng 2.1) Sau d6 so sanh h? sff chfnh xac cua hai chi tit!. . 2. CAP cHiNH xAc Tieu chuffn qui dinh c6 20 cffp chinh xac, duqc ky hi~u la : ITOl, ITO, ITl, ..., IT18. Trong d6: ■ Cffp chinh xac ITl + IT4 : duqc sir dvng d6i voi cac chi tie't yeu c~u d◊ chinh xac rfft cao nhu' cac kich thu'oc mfiu chuffn, dvng C\l do. ■ Cffp IT5+ IT6 : sir dvng trong linh vgc co khi chinh xac. ■ Cffp IT7 + ITS : sir d1;mg trong linh vrf.c co khi thong dvng. ■ Cffp IT9+ ITl 1 : sir dvng trong ITnh vrf.c co khi Ion. ■ Cffp IT12+ IT16: sir dvng d6i voi chi tie't yeu c~u gia cong tho. ■ 3. H:¢ THONG LAP GHEP A. H~ tho'ng 16 H? thdng 18 la t(lp h(Jp tdt ca cac kiiu ldp ma vi tri mdn dung sai 18 la cd djnh, con miin dung sai trµc thay aili tuy theo kiiu ldp. Sai l?ch Cd bdn cua 18 Cd ban ky hi? u H (EI = 0 ). Mien dung sai cua tn,ic 0uong o i!!! .s::: Cl C: .s::: Mien dung sai cua lo Cd ban C: ti$ "O ~ B. H~ tho'ng trl}c H? thdng trµc la t(ip h{/p tdt ca cac kiiu ldp ma vj tri miin dung sai trµc la c{l djnh, con mien dung sai 18 thay d6i tuy theo kilu ldp. Mien dung sai cua 16 Cd ban cua trl!,C Sai l?ch cd bdn ky hi?u h (es= 0). 0uong o ,£!:! .c Cl C: .s
  16. 15 4. Sai l~ch cd ban Tieu chuin c6 28 sai lc$ch co ban cua 16 va 28 sai lc$ch co ban cua tn;ic du9c ky hic$u b~ng m9t (ho~c hai) chu cai b~t d~u tu a, b, c, ... , za, zb, zc. Trong d6 chu hoh ky hic$u cho 16 (chi tie't bao) va chu thuong ky hic$u cho tn.ic (chi tie't bi bao ). 0) C: m . 'O ':::, "'O .c: Alm (.) .
  17. 16 5. Ldp ghep tieu chuiln TCVN2244 - 99 da quy dµili m9t day ki6u l~p ghep trong h~ th5ng 16 co ban va h~ th5ng tr\lc co ban. Cac ki6u l~p nay du dap ung yeu diu san xuilt. Bang2.2 & ., A. ~ ~ ., ' ~ LAP GHEP TRONG HE. THONG LO VOi KTDN TU 1 DEN 500mm' TCVN 2245 - 99 L6 Sai l~ch Cd ban cua tr\IC Co a b C d e f g h Js Ban L~p ghep H5 H5 H5 HS - - - g4 h4 js4 H6 H6 H6 H6 H6 - - - - /6 g5 h5 Js5 H7 H7 H7 H7 H8 H7 H7 H7 H7 - - - - - - - - c8 d8 e7 e8 /7 g6 h6 ] 8 6 H8 H8 H8 H8 H8 H8 H8 H8 - - - - - - - - I c8 d8 e8 /7 /8 h7 h8 Js7 H8 H8 H8 H9 H8 - - - - d9 e9 /9 h9 H9 H9 H9 H9 H9 H9 H9 H9 - - - - - - - d9 e8 e9 /8 /9 h8 h9 HlO HlO HlO HlO - - - dlO h9 hlO Hll Hll Hll Hll Hll Hll - - - - - all bll ell dll hll H12 Hl2 Hl2 - - bl2 hl2 L6 Sai l~ch Cd ban cua tr\IC Co k m n p r s t u V X z ' Ban L~p g;hep H5 H5 H5 H5 - - - k4 m4 n4 H6 H6 H6 H6 H6 H6 H6 - - - - - - k5 m5 n5 p5 r5 s5
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